CVE-2026-65789CriticalRevised 8 Sep

Windows DNS Server Remote Code Execution Vulnerability

Assessment

Use after free in Windows DNS allows an unauthorized attacker to execute code over a network.

Severity: Critical
CVSS base score: 8.1CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
Impact: Remote Code Execution
EPSS, next 30 days: 0.7%Higher than 51.5% of scored CVEs · FIRST model run 26 Sep 2026 · about EPSS
Exploitability: Exploitation Unlikely
Publicly disclosed: No
Customer action: Required: apply the update
Component: Windows DNS
Weakness: CWE-416: Use After Free
Issued by: Microsoft
Published: 11 Aug 2026 · August 2026
Last revised: 8 Sep 2026Updated software table to remove clients versions because this vulnerability only impacts Windows Servers. This is an informational change only.

6 KBs

KB	Type	Restart	Applies to	Other CVEs
KB5120228	Security Hotpatch Update	Required	Windows Server 2025, Windows Server 2025 (Server Core installation)	All CVEs in KB5120228
KB5120229	Security Hotpatch Update	Required	Windows Server 2022, Windows Server 2022 (Server Core installation)	All CVEs in KB5120229
KB5120233	Security Update	Required	Windows Server 2025, Windows Server 2025 (Server Core installation)	All CVEs in KB5120233
KB5120238	Security Update	Required	Windows Server 2019, Windows Server 2019 (Server Core installation)	All CVEs in KB5120238
KB5120242	Security Update	Required	Windows Server 2022, Windows Server 2022 (Server Core installation)	All CVEs in KB5120242
KB5120418	Security Update	Required	Windows Server 2016, Windows Server 2016 (Server Core installation)	All CVEs in KB5120418

Windows

8 affected products